Fig. 2.

Transseptal approach and posterolateral portal. After implementing the posteromedial portal, the camera is retracted and passed underneath the anterior cruciate ligament and into the PL recessus visualizing the dorsal septum from the lateral side (a). A shaver (Excalibur®, Arthrex, Naples, FL, USA) is introduced through the posteromedial portal to create a transseptal approach under indirect visualization (b). Through the transcondylar view, size and position of the transseptal portal can be validated (c). To access the PL recessus, the arthroscope is placed into the PM portal and passed through the transseptal approach (d). Under direct visualization a PL portal is created, analogously to the PM portal (e, f). In case of revision surgery with extensive scarring or decreased opening of the medial joint space, primary visualization of the dorsal septum from the medial side may be required. Therefore, the arthroscope is first passed through the AL portal, underneath the PCL and into the posteromedial recessus, in order to observe resection of the septum. DS dorsal septum, LFC lateral femoral condyle, PHLM posterior horn of the lateral meniscus, MFC medial femoral condyle, PMJC posteromedial joint capsule, PLJC posterolateral joint capsule, PMF popliteomeniscal fibers